Beryllium (Be)
Beryllium was discovered as an oxide in both beryl and emeralds in 1798. Beryllium is found in bertrandite, beryl, chrysoberyl, phenacite, and many other minerals.
The metal, steel-gray in color, is one of the lightest metals and has a high melting point. More elastic than steel, it is non-magnetic, resists concentrated nitric acid, and has excellent thermal conductivity. Beryllium and its salts are toxic and must be handled with care.
Beryllium copper alloy is used for springs, electrical contacts, spot-welding electrodes, and non-sparking tools. The element is also used as a structural material for high-speed aircraft, spacecraft, satellites, and missiles.